Tag archives: canine genetic disease testing

After many inquiries by our wonderful clients, Paw Print Genetics is excited to announce that we have begun testing for two genetic mutations reported to cause progressive retinal atrophy in the golden retriever. Known specifically as progressive retinal atrophy, GR1 and GR2 (PRA-GR1 and PRA-GR2), these two diseases were found to be caused by genetic mutations in the SLC4A3 and TTC8 genes, respectively. In addition to the golden retriever, the TTC8 mutation that causes PRA-GR2 has also been identified in a clinically affected Labrador retriever.

Progressive retinal atrophy (PRA) is not a single disease, but rather a group of inherited diseases each caused by different genetic mutations in different genes. The various forms of PRA affect over 100 different dog breeds. Though there are variations in the progression of disease, most varieties of PRA (regardless of genetic cause) result in blindness due to an inherited degeneration of the retina; more specifically, the degeneration of retinal cells known as rods and cones, which play an important role in vision.

In PRA-GR1 and PRA-GR2, signs of night blindness and loss of peripheral vision are seen first with progression to complete blindness occurring over time. In addition, they are both considered late onset ...

One of the hottest questions from our loyal, Paw Print Genetics clients over the past several months has been, “When are you going to offer genetic testing for hereditary cataracts?” After much preparation and anticipation, we are happy to report that Paw Print Genetics has begun testing for two different mutations of the HSF4 gene reported to cause hereditary cataracts (HC) in seven different breeds of dog.

Cataract is the term used to describe a condition in which opacities develop in the normally clear lens of the eye. The lens is responsible for focusing light onto the retina in the back of the eye resulting in acute, focused vision. With cataracts, the lens cannot focus light appropriately. This results in progressive vision deficits as the cataract increases in severity. While many cataracts identified in dogs are caused by non-inherited causes (e.g. UV radiation, infections, diabetes, chronic inflammation of the eye), as the name suggests, HCs are those passed from generation to generation. In addition, inherited genetic mutations are the most common cause of cataracts in dogs. However, by performing genetic testing on dams and sires prior to breeding, selective breeding precautions can be taken to prevent affected puppies ...

While the history of the beagle’s early breed development has been lost due to lack of record keeping, the mid to late 1800’s saw the arrival of the modern beagle on the shores of North America. From its English homeland where it was developed to hunt rabbits and other small game, the beagle has become one of the most popular breeds in the United States, ranking 4^th overall in the 2013 American Kennel Club’s registration statistics. Behind their charming, deep throated vocalization known as baying, lies a social, even tempered and jovial dog breed suited for modern family life. Unfortunately, like other purebred dogs, the beagle is known to inherit some genetic diseases that can dampen the spirits of this normally energetic and fun-loving breed. One such inherited disease of beagles is known as Musladin-Lueke syndrome (MLS), a multi-systemic disease of connective tissue.

Named after beagle breeders Tony and Judy Musladin and Ada Lueke, MLS was first reported in the 1970’s and has now been identified in multiple countries including England, Australia, America and Japan. In 2010, a genetic mutation in the ADAMTSL2 gene was found to be responsible for the unique clinical signs of this disease. Though not ...

Subvalvular aortic stenosis (SAS), one of the most common inherited cardiac diseases in dogs, is a major concern for many owners of large breed dogs including the Newfoundland, golden retriever, American Staffordshire terrier and Rottweiler. SAS is caused by an abnormal ring or ridge of tissue in the left ventricle of the heart resulting in a partial obstruction of the left ventricular outflow tract; the pathway that allows blood to flow from the left ventricle, through the aortic valve and into the aorta which carries oxygenated blood to the body. In mild cases, dogs live a normal life, free of clinical signs related to the vessel narrowing. However, in moderate to severe cases of SAS, the increased strain placed upon the heart to pump blood through the partially obstructed aortic valve can result in structural changes of the heart muscle, congestive heart failure, arrhythmias and sudden death. SAS also predisposes dogs to development of potentially lethal bacterial infections of the aortic valve. Unfortunately, it is not possible to predict the severity of disease in puppies by examining the hearts of affected parents. Mildly affected parents can have severely affected puppies and vice versa. On average, SAS-affected dogs only live to ...

From their ancient Egyptian roots depicted in carvings of their predecessors, the speed and agility of the greyhound has long fascinated humans who found great potential in the breed as hunting companions, and much later, as fantastic family dogs. Like other members of the large grouping of dog breeds known as sighthounds, it was obvious to their ancient human handlers that the greyhound’s exceptional athletic skill, lean muscular body, and keen vision could be invaluable for hunting both large and small game. While it is no longer as common for greyhounds to be used for hunting, their docile temperament outside of the hunt contributed to an easy transition to the more domestic lifestyle most greyhounds now live. Though able to run 40 miles per hour when properly conditioned, with regular exercise the greyhound is just as content taking it easy with their human family members. Despite their majestic appearance and impressive athletic attributes, like other purebred dogs, greyhounds are known to inherit some genetic diseases that may keep this talented runner at the starting block. One such disease, known as greyhound polyneuropathy (GP), is caused by a mutation in the NDRG1 gene.

GP is a severe, progressive neurological disease similar ...

Since the first exhibitions of the modern basset hound in the late 19^th century, their mellow and charming personality has made them a popular family dog. Though according to the Basset Hound Club of America, it is not unusual for a basset hound to be a little stubborn or to have “selective hearing” (especially if following a scent trail), this minor annoyance is easily tempered by their affectionate and sensitive disposition. Originally bred for hunting with a person on foot, the basset hound’s short legs kept them from outrunning their handler while following their exceptional nose. Unfortunately, like other purebred dogs, the basset hound has also been unable to outrun susceptibility to certain inherited diseases. One such condition is a disease of blood platelets known as thrombopathia that occurs due to a mutation in the RASGRP1 gene.

Dogs affected with thrombopathia produce a dysfunctional form of a protein important in the aggregation of platelets during blood clotting. The resulting inability to produce functional blood clots leads to easy bruising and frequent episodes of spontaneous bleeding from the gums, nose, and the gastrointestinal tract. Affected dogs may also show signs of lameness due to spontaneous bleeding in joints. Loss of ...

As I discussed in a previous blog, the US and the UK have a soft spot in their heart for the Cavalier King Charles spaniel (CKCS). The popularity of the breed has exploded over the past 15 years and is continuing to climb the AKC registration statistics. In 2013, the CKCS moved up to the 18^th most popular dog registered with the AKC (up from 20^th place in 2012 and 40^th place in 2002). With this gain in popularity comes a larger number of owners voicing their concern about inherited diseases that affect the breed. However, through the use of modern genetic testing technology, some inherited diseases can be completely eliminated. One such inherited disease is dry eye curly coat syndrome (DECC); a disease caused by a mutation in the FAM83H gene and unique to the CKCS.

To the knowledgeable eye, dogs affected with DECC can often be identified at birth (or shortly after) due to the presence of a rough or curly coat which does not grow well initially. Following eyelid opening, affected dogs will have frequent, recurring episodes of conjunctivitis sometimes accompanied by painful ulceration of the corneas due to the inability to produce adequate ...

The Italian greyhound (IG) is a wonderful breed. As a true greyhound, the IG is happiest when provided an opportunity to exercise frequently. However, in their down time IGs are just as content laying on the couch with their human family. Their sweet demeanor combined with easy grooming has made this breed desirable to many. Unfortunately however, like most pure bred dogs, the IG can develop a handful of inherited diseases that make life a challenge for the breed and those that love them.

It isn’t a secret among IG aficionados that one of the biggest health concerns for the breed is their oral health. Though the exact reason is yet to be fully understood, it is not uncommon for IGs to develop early-onset dental disease resulting in significant problems in early adulthood. Though a commitment to daily tooth brushing can help prevent many dental issues, there is also an inherited dental disease in IGs that can now be eliminated through genetic testing of dams and sires prior to breeding!

In the “Health Concerns” section of the Italian Greyhound Club of America website, there is a discussion about “a condition in IG's where the teeth are small ...